Four-dollar gasoline is causing some sharp turns in thinking.

Breaking with the policy of his father, President Bush has asked Congress to permit offshore exploration and drilling, likely due to the surge in energy prices.

The deep waters off the Eastern Gulf of Mexico, the Atlantic Coast, the Pacific Coast, and a small section of Alaska have been protected by a congressional moratorium since 1982, which prohibits oil and gas leasing on most of the outer continental shelf—an area from three miles to 200 miles offshore.

While the current president has made no secret of his support for greater domestic oil exploration, such offshore drilling has in the past been strongly opposed by the Bush family: As president, George H.W. Bush bolstered the congressional ban with an executive order in 1990, and former Florida governor Jeb Bush was a vocal opponent of offshore drilling during his time in office.

But Bush's request to repeal the moratorium fits squarely with comments on the subject made by presumptive Republican presidential nominee John McCain in Houston on Tuesday.

The Minerals Management Service, the government agency that regulates domestic energy production off America's coast, estimates there are 19 billion barrels of oil offshore that have not been exploited because of the congressional moratorium, along with 86 trillion cubic feet of natural gas (the United States consumes about 7.6 billion barrels of crude oil annually). The agency notes that because drilling methods have improved greatly since exploration was undertaken 25 years ago, there may be even more than currently believed.

The presumptive Democratic presidential nominee, Barack Obama, supports upholding the ban on drilling; Congressional Democrats also reject Bush's proposal, saying oil companies already have 68 million acres of offshore waters under lease that are not being developed.

Although Bush cited current energy prices as the prime motivator for increasing offshore drilling territory, if the ban were to be repealed, relief would still be far off.

"Once a lease sale is held, it could take five to 10 years for drilling to commence. Production could take another five years or more after a discovery," the Minerals Management Service said in a 2006 report to Congress.

While Bush's request will put pressure on Congress to reexamine the continental shelf leasing policy, the president has said he won't lift the presidential ban on drilling until Congress lifts its ban. Both actions are necessary for the moratorium to be lifted.